Class DbMetadata

Namespace

Quartz.Impl.AdoJobStore.Common

Assembly

Quartz.dll

Metadata information about specific ADO.NET driver library. Metadata is used to create correct types of object instances to interact with the underlying database.

public sealed record DbMetadata : IEquatable<DbMetadata>

Inheritance

object

DbMetadata

Implements

IEquatable<DbMetadata>

Inherited Members

object.Equals(object)

object.Equals(object, object)

object.GetHashCode()

object.GetType()

object.ReferenceEquals(object, object)

object.ToString()

Remarks

An init-only record: a description is built once — with an object initializer, or copied with a with expression — and cannot drift afterwards. Everything on it is something you say about a driver. The reflection lookups that description implies — DbBinaryTypeName resolved against ParameterDbType, the property ParameterDbTypePropertyName names on ParameterType, and BindByName on CommandType — are Quartz's own, and are internal.

They replace the old two-phase Initialize() that had to be remembered. A description that cannot work still fails where it is made rather than at the first binary parameter: every lookup is performed once, as the metadata is registered.

Every Type here is optional, because a description only needs them when Quartz has to construct the driver's objects — which is what DbProvider does and what a trimmed application cannot rely on. A description handed to ProviderFactoryDbProvider or DataSourceDbProvider gets its connections, commands and parameters from the factory or the data source, so it names no type at all; what is left is the driver's parameter naming, and the two typed seams below for a driver that needs a command or a binary parameter configured in a way Quartz cannot name.

Properties

AssemblyName

Gets the name of the assembly that holds the connection library.

public string? AssemblyName { get; init; }

Property Value

string

The name of the assembly.

BindByName

Gets a value indicating whether parameters are bind by name when using ADO.NET parameters.

public bool BindByName { get; init; }

Property Value

bool

true if parameters are bind by name; otherwise, false.

CommandType

Gets the type of the command.

[DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.PublicConstructors|DynamicallyAccessedMemberTypes.PublicProperties)]
public Type? CommandType { get; init; }

Property Value

Type

The type of the command.

Remarks

DbProvider constructs one of these per command it runs and, for a driver that binds parameters by name, sets BindByName on it.

ConfigureBinaryParameter

Applied to a parameter carrying a binary column, in place of writing DbBinaryTypeName to the property ParameterDbTypePropertyName names.

public Action<DbParameter>? ConfigureBinaryParameter { get; init; }

Property Value

Action<DbParameter>

Remarks

The same reasoning as ConfigureCommand, for the one parameter type Quartz asks for by name. It matters most on Oracle, where Binary means OracleDbType.Raw and caps a job data map at two kilobytes: parameter => ((OracleParameter) parameter).OracleDbType = OracleDbType.Blob is what an application says instead.

Set, it wins over the reflective setter; with neither, a binary parameter is bound as plain Binary and the driver maps it.

ConfigureCommand

Applied to every command Quartz mints for this driver, in place of the reflective BindByName probe.

public Action<DbCommand>? ConfigureCommand { get; init; }

Property Value

Action<DbCommand>

Remarks

Quartz sets BindByName on the managed Oracle driver's command by looking the property up on CommandType, because it cannot name OracleCommand. A description that names no command type — one behind a DbProviderFactory or a DbDataSource — has nothing to look the property up on, so it says what to do instead: command => ((OracleCommand) command).BindByName = true, in the application, which references the driver and can name the type.

Set, it wins: the reflective probe is not attempted at all, and BindByName is left to the parameter naming it also governs.

ConnectionType

Gets the type of the connection.

[DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.PublicConstructors)]
public Type? ConnectionType { get; init; }

Property Value

Type

The type of the connection.

Remarks

DbProvider constructs one of these per connection it opens, so the type has to keep its public constructors through trimming.

DbBinaryTypeName

Gets the type of the db binary column. This is a string representation of Enum element because this information is database driver specific.

public string? DbBinaryTypeName { get; init; }

Property Value

string

The type of the db binary.

ExceptionType

Gets the type of the exception that is thrown when using driver library.

public Type? ExceptionType { get; init; }

Property Value

Type

The type of the exception.

ParameterDbType

Gets the type of the database parameters.

public Type? ParameterDbType { get; init; }

Property Value

Type

The type of the parameter db.

ParameterDbTypePropertyName

The name of the property on ParameterType that carries a parameter's database type, which DbBinaryTypeName is set through.

public string? ParameterDbTypePropertyName { get; init; }

Property Value

string

Typically "DbType", or the provider's own, such as "SqlDbType".

Remarks

Required exactly when DbBinaryTypeName is set, and unread otherwise — which is why it is nullable rather than required: a provider whose parameters need no explicit database type sets neither. Leaving it out while naming a binary type is reported at startup, naming the database, as every other half-configured provider is.

ParameterNamePrefix

Gets the parameter name prefix.

public string? ParameterNamePrefix { get; init; }

Property Value

string

The parameter name prefix.

ParameterType

Gets the type of the parameter.

[DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.PublicProperties)]
public Type? ParameterType { get; init; }

Property Value

Type

The type of the parameter.

Remarks

The property ParameterDbTypePropertyName names is looked up on this type.

ProductName

Gets the name of the product.

public string? ProductName { get; init; }

Property Value

string

The name of the product.

UseParameterNamePrefixInParameterCollection

Gets a value indicating whether [use parameter name prefix in parameter collection].

public bool UseParameterNamePrefixInParameterCollection { get; init; }

Property Value

bool

true if [use parameter name prefix in parameter collection]; otherwise, false.

Methods

GetParameterName(string)

Gets the name of the parameter which includes the parameter prefix for this database.

public string GetParameterName(string parameterName)

Parameters

parameterName string

Name of the parameter.

Returns

string

Remarks

Called once per parameter bound, which is seven times for a trigger acquisition and fifteen for a trigger write, and it was a concatenation each time. The set of names is small and settled — the statements name about eighty-five between them, and the generated ones (tkn000, oldState00, excludedJobType0000) are bounded by the predicate sizes — so each spelling is worked out once and handed back thereafter.